It's a holdover from the middle ages. Kings owned the country and if someone disagreed you better have an army to make a good argument. Land was then doled out to lords and lesser tenants in exchange for services and goods. That got gradually turned into a state guaranteeing ownership by force and a market system. Overthrowing it ends up giving a temporary reprieve and just replacing the figure head.

Other systems exist but they got crushed by the current system. Cryptocurrency and other ways of ownership seem to evolve to a digital lords owning the majority so long term not making a big difference.